Quick answers
- Which hospitals does William J. Stephan work at?
- Medicare's official clinician data lists William J. Stephan at 4 hospitals: Edward Hospital, Elmhurst Memorial Hospital, Northwestern Medicine Central Dupage Hospital and Northwestern Medicine Delnor Community Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does William J. Stephan see patients?
- Medicare's clinician data lists 3 practice locations, including Naperville, IL and Plainfield, IL. Call before your visit to confirm the address.
- What is William J. Stephan's specialty?
- Medicare lists Interventional Cardiology as the primary specialty, and also Cardiovascular Disease (Cardiology).
- Does William J. Stephan accept Medicare assignment?
- Yes. Medicare's clinician data says William J. Stephan accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for William J. Stephan?
- (630) 600-0700, as listed in official Medicare / NPI Registry data.
- What is William J. Stephan's NPI number?
- 1851344931. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where William J. Stephan works
Medicare's Facility Affiliation Data lists William J. Stephan at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Edward HospitalNaperville, IL · Acute Care Hospital · CCN 140231
- Elmhurst Memorial HospitalElmhurst, IL · Acute Care Hospital · CCN 140200
- Northwestern Medicine Central Dupage HospitalWinfield, IL · Acute Care Hospital · CCN 140242
- Northwestern Medicine Delnor Community HospitalGeneva, IL · Acute Care Hospital · CCN 140211
Practice locations
Addresses where William J. Stephan is enrolled with Medicare (CMS data updated 2026-10-02).
- 10 Martin Ave, Suite 200Naperville, IL 60540 (630) 600‑0700
- 16519 S Route 59, Suite APlainfield, IL 60586 (630) 600‑0700
- 801 S Washington StNaperville, IL 60540 (312) 355‑0450
Group practices
Medicare enrollment lists William J. Stephan as a member of these groups (CMS data updated 2026-10-02).
- Edward Hospital96 clinicians in the group
- Cardiovascular Institute Gpe Inc51 clinicians in the group
Specialties
Other interventional cardiologists in Naperville
Clinicians with the same Medicare primary specialty in Naperville, IL — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Tufts University School Of Medicine |
| Graduation year | 1987 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1851344931 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians